nicolas/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Revert "[InlineFunction] Update metadata on loads that are return values"

Browse Source 
This reverts commit 1d0f757904 because of
https://bugs.llvm.org/show_bug.cgi?id=45590. Needs investigation.
This commit is contained in:
Anna Thomas
2020-04-17 17:11:21 -04:00
parent 7cb1aa9d93
commit ef49b1d97e
2 changed files with 9 additions and 146 deletions
Download Patch File Download Diff File Expand all files Collapse all files

52
llvm/lib/Transforms/Utils/InlineFunction.cpp
View File

@@ -88,10 +88,6 @@ static cl::opt<bool> UpdateReturnAttributes(
"update-return-attrs", cl::init(true), cl::Hidden,
cl::desc("Update return attributes on calls within inlined body"));
static cl::opt<bool> UpdateLoadMetadataDuringInlining(
"update-load-metadata-during-inlining", cl::init(true), cl::Hidden,
cl::desc("Update metadata on loads within inlined body"));
static cl::opt<unsigned> InlinerAttributeWindow(
"max-inst-checked-for-throw-during-inlining", cl::Hidden,
cl::desc("the maximum number of instructions analyzed for may throw during "
@@ -1173,8 +1169,8 @@ static AttrBuilder IdentifyValidAttributes(CallBase &CB) {
return Valid;
}
static void AddReturnAttributes(CallBase &CB, ValueToValueMapTy &VMap) {
if (!UpdateReturnAttributes && !UpdateLoadMetadataDuringInlining)
static void AddReturnAttributes(CallSite CS, ValueToValueMapTy &VMap) {
if (!UpdateReturnAttributes)
return;
AttrBuilder Valid = IdentifyValidAttributes(CB);
@@ -1183,32 +1179,18 @@ static void AddReturnAttributes(CallBase &CB, ValueToValueMapTy &VMap) {
auto *CalledFunction = CB.getCalledFunction();
auto &Context = CalledFunction->getContext();
auto getExpectedRV = [&](Value *V) -> Instruction * {
if (UpdateReturnAttributes && isa<CallBase>(V))
return dyn_cast_or_null<CallBase>(VMap.lookup(V));
if (UpdateLoadMetadataDuringInlining && isa<LoadInst>(V))
return dyn_cast_or_null<LoadInst>(VMap.lookup(V));
return nullptr;
};
MDBuilder MDB(Context);
auto CreateMDNode = [&](uint64_t Num) -> MDNode * {
auto *Int = ConstantInt::get(Type::getInt64Ty(Context), Num);
return MDNode::get(Context, MDB.createConstant(Int));
};
for (auto &BB : *CalledFunction) {
auto *RI = dyn_cast<ReturnInst>(BB.getTerminator());
if (!RI)
if (!RI || !isa<CallBase>(RI->getOperand(0)))
continue;
auto *RetVal = cast<CallBase>(RI->getOperand(0));
// Sanity check that the cloned RetVal exists and is a call, otherwise we
// cannot add the attributes on the cloned RetVal.
// Simplification during inlining could have transformed the cloned
// instruction.
auto *NewRetVal = getExpectedRV(RI->getOperand(0));
auto *NewRetVal = dyn_cast_or_null<CallBase>(VMap.lookup(RetVal));
if (!NewRetVal)
continue;
auto *RetVal = cast<Instruction>(RI->getOperand(0));
// Backward propagation of attributes to the returned value may be incorrect
// if it is control flow dependent.
// Consider:
@@ -1236,26 +1218,10 @@ static void AddReturnAttributes(CallBase &CB, ValueToValueMapTy &VMap) {
// with a differing value, the AttributeList's merge API honours the already
// existing attribute value (i.e. attributes such as dereferenceable,
// dereferenceable_or_null etc). See AttrBuilder::merge for more details.
if (auto *NewRetValCB = dyn_cast<CallBase>(NewRetVal)) {
AttributeList AL = NewRetValCB->getAttributes();
AttributeList NewAL =
AL.addAttributes(Context, AttributeList::ReturnIndex, Valid);
NewRetValCB->setAttributes(NewAL);
} else {
auto *NewLI = cast<LoadInst>(NewRetVal);
if (CB.isReturnNonNull())
NewLI->setMetadata(LLVMContext::MD_nonnull, CreateMDNode(1));
// If the load already has a dereferenceable/dereferenceable_or_null
// metadata, we should honour it.
if (uint64_t DerefBytes = Valid.getDereferenceableBytes())
if(!NewLI->getMetadata(LLVMContext::MD_dereferenceable))
NewLI->setMetadata(LLVMContext::MD_dereferenceable,
CreateMDNode(DerefBytes));
if (uint64_t DerefOrNullBytes = Valid.getDereferenceableOrNullBytes())
if (!NewLI->getMetadata(LLVMContext::MD_dereferenceable_or_null))
NewLI->setMetadata(LLVMContext::MD_dereferenceable_or_null,
CreateMDNode(DerefOrNullBytes));
}
AttributeList AL = NewRetVal->getAttributes();
AttributeList NewAL =
AL.addAttributes(Context, AttributeList::ReturnIndex, Valid);
NewRetVal->setAttributes(NewAL);
}
}